1. Field of the Invention
The present invention relates generally to an article of footwear and more particularly to an asymmetric article of footwear.
2. Description of Related Art
In many sports, an athlete uses his or her feet in an asymmetric fashion, where different parts of the foot are used at varying times for different purposes, either intentionally or unintentionally. For example, a runner develops unique wear patterns on the outsoles of his or her running shoes due to how a particular runner impacts and rolls the shoes on the ground with each stride. Each runner's wear pattern will be slightly different, depending upon how the runner subconsciously chooses to control the motion of his or her feet for a comfortable and stable running experience.
In another example, the motions of the feet are asymmetric for a more intentional purpose, such as in fencing. The basic moves of fencing include lunging forward from an upright position. The direction of the forward motion is selected by the leading foot, which is lifted during the lunge and then impacts the fencing surface. The trailing foot anchors and stabilizes the fencer, and typically slides on the fencing surface for much of the lunge. Upon retreating, both feet are typically dragged across the fencing surface. During a fencing bout, the leading foot guides the play by rolling, flexing, and dragging in a number of directions. The trailing foot also flexes and drags, but in a fewer number of positions. The toe region of the leading foot is particularly flexed and dragged, with the medial side of the toe region being dragged more than the lateral side of the toe region.
These typical and asymmetrical fencing foot motions result in wear patterns that vary over the shoes. The shoe on the leading foot will experience wear on the heel, due to impact and on the medial side toe region, due to dragging. The shoe on the trailing foot will experience more uniform wear.
Asymmetric foot motions are not only used by athletes. For orthopedic reasons, a foot may drag on one side more than on the other. For example, if a person has limited use of one foot or leg, the foot may drag, causing one side of the shoe to wear more significantly than the other. Such a situation may occur due to accident, disease, childhood conditions, such as being pigeon-toed or bow-legged, or the like.
Efforts have been made to account for asymmetrical motions between the feet in fencing shoes. For example, U.S. Pat. No. 6,430,847 discloses using different shoes for the leading and trailing foot, to account for the asymmetric motions of one foot with respect to the other foot. This is to allow each foot to perform optimally.
However, there remains a need in the art for a shoe which accounts for the asymmetric motions of a foot, such as how the leading foot of a fencer tends to be dragged more on the medial side of the toe region and flexed more on the lateral side of the toe region.